Abstract: Stress in the wall of a pipe (12) is measured using a pig (10) carrying at least one linear array of probes, so that the probes (30) in the array pass in succession over a location on the pipe wall. Each probe (30) comprises an electromagnetic core (32) with two spaced apart electromagnetic poles (34), and a magnetic sensor (36) arranged to sense the reluctance of that part of the magnetic circuit between the poles (34), and an alternating magnetic field is generated in the electromagnet means and consequently in the pipe wall. Successive probes (30) in the array are oriented differently so that the corresponding orientations of the magnetic field in the pipe wall are different. Preferably the probes (30) also include sensors (38) between the two poles (34) to sense magnetic flux perpendicular to the direction of the free space magnetic field between the poles. The signal from the sensor (36) and (38) enable the stress to be determined. Such an array may be used with any long object of ferromagnetic material.

Abstract: The variation in properties of a ferromagnetic material with depth below the surface is assessed in a nondestructive fashion using a probe that incorporates an electromagnet. An alternating magnetic field is generated in the electromagnet and so in the object, and a magnetic sensor is arranged to sense a magnetic field due to the electromagnet. Signals from the magnetic sensor are analysed into an in-phase component and a quadrature component, and these are mapped directly into material property and lift-off components; this analysis enables accurate measurements of material property (such as stress) to be distinguished from changes in lift-off. The measurements are repeated for at least five different frequencies of the alternating magnetic field; and the measurements at different frequencies are deconvolved assuming a functional form for the variation of material property with depth, the function having no more than five unknown constants. The stress at depths for example in the range 0.5 mm to 5.

Abstract: A chemical plant for performing a chemical reaction between particles of a material such as lithium metal, and a reagent such as butyl chloride in solution in hexane, in which one reaction product is a solid material, includes a reaction vessel (12). Several ultrasonic transducers (16) are attached to a wall of the vessel (12) so as to irradiate ultrasonic waves into the vessel, the vessel being large enough that each transducer irradiates into fluid at least 0.1 m thick, each transducer irradiating no more than 3 W/cm2, and the transducers being sufficiently close to each other and the number of transducers being sufficiently high that the power dissipation within the vessel is at least 10 W/liter but no more than 200 W/liter. The high intensity of ultrasound ensures that lithium chloride is cleaned off the surface of lithium metal particles throughout the vessel (12).

Abstract: A power supply and control system for a motor vehicle incorporating a plasma-assisted reactor for treatment of exhaust emissions and including a power source for supplying first and second output voltages.

Abstract: A dielectric welding apparatus for welding a plastic sleeve contains a solid state radio frequency generator linked via a matching network to a welding tool. The tool (30) includes a frame (35) with a handle (36), the frame defining a slot in which are opposed welding electrodes (40, 44), the slot being open at one end and at the other end communicating with a wider aperture (39). A pneumatic cylinder (48) can be actuated to urge the electrodes together, both the cylinder (48) and the RF generator (66) being activated by a trigger (50) on the tool (30). The electrodes are coated with an electrically insulating material that is not dielectrically heated, and are readily removable, so they can be replaced, for example when the electrically insulating coating becomes worn.

Abstract: An environmental radioactivity monitor comprises a filter (12) through which air is caused to flow, and a detector (13) of radiation emitted from the particles trapped on the filter. The signals from the radiation detector are analyzed into a multiplicity of energy channels, for example with a multi-channel analyzer (22), the counts in at least two energy windows (W1, W2; W3, W4) being used to determine the shapes of the low-energy tails of the peaks of the naturally occurring radio-nuclides ThC′ and RaC′, so their effects can be eliminated. The shape of the ThC′ peak is used to predict and strip out the ThC peak, and the shape of the RaC′ peak is then used to predict and strip out the RaA peak, so all background effects are eliminated. Accurate measurements of air-borne radioactivity are hence possible with short counting times.

Abstract: A helm pump (10) rotated either in forward or reverse direction by operating a steering wheel (13) and discharges a liquid of a quantity proportional to the rotating angle, and a double action cylinder moves a rudder (27) and is provided on rudder (27) side of the ship, helm pump (10) and the double action cylinder being connected with the hydraulic circuit of fully closed construction, to move the rudder (27) by an amount corresponding to the amount of liquid discharged from the helm pump (10). A second pump generates discharging pressure in the same direction as the discharging direction from helm pump (10) against resistive pressure generated by the rotation of helm pump (10) due to the operation of steering wheel (13) is installed in series in part of the fully closed hydraulic circuit, so the steering resistance of steering wheel (13) is automatically reduced by the action of the second pump.

Abstract: A break in a rail, where two rails (12, 13) extend parallel to each other along a railway line, is detected by connecting the two rails together electrically with two electrical connections (16, 18) at opposite ends of a section of the line, causing electrical currents to flow in parallel along the two rails from a current source (22), and detecting (24) the currents flowing in each of the rails (12, 13). From the two values of current one can find it there is a break in one of the rails (12, 13). The currents may be measured in one of the connections (16). The current source (22) may be DC or low frequency AC, or a coded pulse sequence.

Abstract: A modular corona discharge reactor in which individual reactor chambers are arranged vertically and are grouped in serial pairs.

Abstract: Capsules, for example for the delivery of pharmaceuticals, are produced from two films (18) of a water-soluble polymeric material, by deforming the films to form a multiplicity of recesses, and filling the recesses with a flowable filling material. This is performed using two adjacent rotary dies (14, 15), with recesses (16) into which the films (18) are deformed. The dies (14, 15) also act as electrodes for welding the films together by dielectric welding to form filled capsules (30). The capsules (30) can readily be separated from the resulting web. The polymeric material may be gelatin, or a water-soluble cellulose derivative such as hydroxypropyl methyl cellulose, and may also contain a plasticizer.

Abstract: A method and device for producing visually sensed images of the internal structure of, particularly, a biological object. When used for diagnostic purposes in medicine the x-ray dosage of tissues surrounding the spot that is being examined is decreased.

Abstract: Using a solution mining procedure, an ore (10) is treated with a solution of acetic acid and hydrogen peroxide so as to form a leachate containing lead ions. Lead ions (and other metal ions such as zinc and manganese) are stripped (22, 24, 26) by solvent extraction from the leachate to form separate aqueous solutions. The aqueous solution containing lead ions is treated electrochemically in the anodic compartment of a separated electrochemical cell (42) to form a precipitate of lead oxide. Manganese dioxide can be produced similarly (72). A precipitate of zinc hydroxide can be formed in the cathode compartment of a separated electrochemical cell (56). In the cells (42, 72) extracting lead ions and manganese ions, the cathode compartment is used to generate hydrogen peroxide (for use in making the leachant), either directly or indirectly.

Abstract: Cell lysis may be brought about by contacting a suspension of cells with a lysis reagent such as sodium hydroxide solution; subsequent treatment enables organic molecules such as plasmid DNA to be separated from other cell components. Intimate mixing of the cell suspension with lysis reagent is achieved by passage through a fluidic vortex mixer arranged so the residence time of the cell suspension in the mixer is less than the time for lysis to be completed, and may be less than 0.1 seconds. Such a vortex mixer comprises a cylindrical chamber with an axial outlet duct and at least one tangential inlet duct, but with no internal baffles. The low shear stress to which the cell suspension is subjected minimizes loss of product through denaturation or fragmentation of the product, and indeed of contaminants. The subsequent treatment may also utilize a fluidic vortex mixer.

Abstract: For monitoring railway tracks on a frequent basis, instrumentation packages are installed in service vehicles (18), for example in passenger carriages. The instrumentation package (16) comprises sensors (35, 36, 42) mounted on a bogie (24) of the vehicle (18), which provide data to a computer (40). The computer (40) processes the data to characterise the track quality, and stores the results tagged with positional information. At intervals these stored results are automatically transferred by radio to a remote base station (12). An operator at the base station can monitor the track quality daily, and hence advise on cost-effective maintenance schedules.

Abstract: A lens connecting device and a method of connecting lenses for rimless glasses. Connecting means comprises a base plate to which a cylindrical element is provided to project, and a detent opening provided in the base plate. By pressingly inserting a shaft element into an insertion opening of the cylindrical element in a state that the cylindrical element is inserted into a circular-shaped connecting opening, the end part and the base plate can be integrated therewith. The shaft element is provided at the end part of the bracket to project, and the connecting opening is provided in the edge part of the lens. An opening is bored in the lens using the detent opening as a guide means by rotating the end part around the axis of the connecting opening.

Abstract: A process is described for the elimination of hydrogen sulfide from gas mixtures by catalytic oxidation over activated carbon catalyst which converts the hydrogen sulfide to elemental sulfur and water, the former being sorbed by the activated carbon while the latter is transported with the gas mixture and may be removed by known dehydration processes. The above oxidative process is conducted at elevated temperatures and pressures and with sufficient residence time to assure virtually complete conversion of the hydrogen sulfide with minimal production of by-product sulfur dioxide. Traces of heavy hydrocarbons in the feed gas mixture which may reduce the life of the catalyst and the quality of the sulfur product may be removed by cryogenic means or by sorption on an activated carbon guard bed.

Abstract: A reactor for the plasma processing of gaseous media, especially internal combustion engine exhaust, has a bed made of a body of ceramic material a series of gas permeable electrodes embedded within the bed. The electrodes are distributed to provide a predetermined electric field distribution within the bed.

Abstract: An internal combustion engine including an engine block, a power cylinder mounted for revolving within the block and having a reciprocating, non-rotating piston which includes drive pins cooperating with and driving the power cylinder. A cam cylinder cooperates with the power cylinder and each includes ports in the sides thereof which periodically align with each other for forming intake and exhausts ports.

Abstract: If the wheel/rail adhesion for a railway vehicle is insufficient then the wheels may slip when braking. If slipping is detected, a control system may reduce the brake pressure to permit a controlled level of slip and so to optimize the braking force for the available adhesion. By determining the pressure supplied to the brake cylinder, a signal may be obtained which indicates the value of the adhesion. Alternatively the adhesion may be monitored by detecting any discrepancy between the braking deceleration demanded by the driver and the observed deceleration. The adhesion signal may activate a warning. It may also be used to adjust the rate at which sand is supplied by a sander to the wheel/rail interface. The rate at which sand is supplied may also be adjusted in accordance with other parameters such as the train speed.